1. Field of the Invention
The present invention pertains to systems for connecting and disconnecting component parts of a tool or the like, and is particularly applicable to tools and other composite assemblies which must be used in environments in which it is important to maintain positive control over each individual component of the assembly. For example, the invention may be applied to a socket wrench set in which a ratchet wrench handle must be alternately connected to various size sockets and/or extensions. The need for positive control over these various component parts may arise for a number of different reasons in various contexts and environments.
For example, a typical application of the invention may be to tool sets adapted for use in extravehicular activities in the space program. It can readily be appreciated that, if one of the component parts of a tool were dropped during such activity, it would be difficult or impossible to recover, not only due to the low or zero gravity environment, but also due to the bulky protective clothing which must be worn by the user in such environment. Similar problems can occur, for example, in subsurface diving operations as well as other situations in which workers must wear cumbersome gloves and/or other garments to protect against pressure or temperature extremes, hazardous chemicals, physical injury, etc. In still other situations, loss of a component part of a tool may cause damage and/or hazard by falling into moving machinery, onto personnel or other equipment, etc. For example, in one known instance, a wrench socket was inadvertently dropped into a missile silo. After falling approximately 70 feet, the socket ricocheted and punctured a tank, releasing a large quantity of combustible material, and ultimately causing an explosion.
In short, the present invention is especially useful to any situation in which the operator's manual dexterity is hampered, and/or the consequences of losing control of an untethered tool component are, for any reason, unacceptable.
2. Description of the Prior Art
Various schemes have been devised for releasably locking tool components together. These include, for example, screw thread means and spring loaded detent mechanisms of various types. The latter detent mechanisms may be releasable by simply exerting a sufficient separating force, or they may be provided with release mechanisms operated, for example, by push buttons.
These prior mechanisms are unsuitable for the types of environments described hereinabove for a number of reasons. Some such mechanisms, for example screw threaded type mechanisms, are difficult to operate when the user is encumbered by heavy gloves or other protective garments and can only transmit torque in one direction. Conventional detent type mechanisms, on the other hand, may not provide sufficiently positive insurance against accidental separation of the tool components during use. Mechanisms operable by push buttons or the like accessible on the exterior of the tool may be inadvertently operated in use, particularly where the operator has his dexterity encumbered by the environment and/or his protective clothing. Furthermore, the problems in the prior art revolving around difficulty of assembly and disassembly, inadvertent release, etc., are undesirable and bothersome even when the user is working barehanded in an amicable environment.
In any event, none of these prior systems provide any means for controlling or recovering a tool component which may simply be dropped by the user while attempting assembly or disassembly. For the latter purpose, for example in connection with activities in space, tethers have been employed, with each component of the tool having its own respective tether, which may be attached to the user's clothing, to a work station or tool box, or to some other suitable base structure. However, where the tool in question must be operated, e.g. with a rotary or reciprocating motion, such multiple tethers may interfere with the necessary movements and/or become entangled with one another. Swivel rings, movable collars, and the like designed to facilitate the necessary movements of the tool have not been entirely successful in eliminating entanglement of the tethers and similar problems.